Date: Sun, 27 Sep 2009 15:44:06 -0700
From: Stefano Iachella <[email protected]>
Subject: [alfa] Spica pump w/buggered TA mount and gas mileage
Long subject line. Here's the story. Ever since I've owned
my 74 GTV, I've had the same Spica pump. The car has
always run great, even after a fresh Norman head and 10.2mm
cams 6 or 7 years ago. A short time after the rebuild, my
mechanic said, "Y'know the TA mount is all buggered up.
The TA is only held on by one screw. I tune it the best I can."
I inspected it and one screw had snapped off at some point
in the distant past. Someone tried to tap a new hole just off
to the side, but that didn't work out so well for them, so they
left it with only one screw holding the TA on.
I recently started thinking about this again because I never
get more than 135 miles on a tank of gas. I have never figured
out the mileage, but with an 11 gallon tank and putting 9 to 10
gallons each fill that makes something like 14 or 15 mpg. Not
really right for a Spica system unless something is amiss.
Could a poorly seating TA contribute to bad gas mileage? I
have a spare pump that is on the engine I had removed from
my Alfetta when I put in the TS into it. Should I be thinking
seriously about sending this worn pump out to Wes and
installing it on my GTV?
Thanks,
Stefano
Concord, CA
Absolutely, if you're getting 15 mpg, your SPICA pump is running way rich.
But have you checked the linkage gap to be sure it's about .019"? Is the TA
working at all? If you have the original one, it is probably worn out. I'd
check that first, then be sure the one screw is holding the TA flush against
its mount, then do the standard SPICA tune from Wes' book or the AROO tune
written by the late and dearly missed Bob Parry. I'll bet dollars to donuts
the TA is toast.
My Spider's TA mount had an almost-stripped hole when I got it; I tapped it
out next size larger (being careful to catch all the metal removed with
grease on the tap and a bent piece of flat metal coated with grease under
the hole to catch anything that fell through, tho Wes confirmed that in the
logic section there was minimal risk) and it has held fine ever since.
Downside is, I had to drill out the replacement TA for the larger screw to
fit through.
Incidentally, during one of those traffic jams in July heat at the
convention, my electric fan malfunctioned and my new-ish TA got so warm it
puked. Another reason to pay particular attention to overheating in a SPICA
car. And saying it once again, avoid running too cool or the TA will not
extend far enough and your mixture will be too rich.
YM obviously WV
Joe Cantrell
Sono lento, ma sono brutto
Squadra Empirica Crash Test Dummy
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